Support getting file metadata on Windows

tests/pass/shims/windows-fs.rs

@@ -0,0 +1,131 @@
+//@only-target: windows # this directly tests windows-only functions
+//@compile-flags: -Zmiri-disable-isolation
+#![allow(nonstandard_style)]
+
+use std::os::windows::ffi::OsStrExt;
+use std::ptr;
+
+#[path = "../../utils/mod.rs"]
+mod utils;
+
+// Windows API definitions.
+type HANDLE = isize;
+type BOOL = i32;
+type DWORD = u32;
+type LPCWSTR = *const u16;
+
+const GENERIC_READ: u32 = 2147483648u32;
+const GENERIC_WRITE: u32 = 1073741824u32;
+pub const FILE_SHARE_NONE: u32 = 0u32;
+pub const FILE_SHARE_READ: u32 = 1u32;
+pub const FILE_SHARE_WRITE: u32 = 2u32;
+pub const OPEN_ALWAYS: u32 = 4u32;
+pub const OPEN_EXISTING: u32 = 3u32;
+pub const CREATE_NEW: u32 = 1u32;
+pub const FILE_ATTRIBUTE_DIRECTORY: u32 = 16u32;
+pub const FILE_ATTRIBUTE_NORMAL: u32 = 128u32;
+pub const FILE_FLAG_BACKUP_SEMANTICS: u32 = 0x02000000u32;
+
+#[repr(C)]
+struct FILETIME {
+    dwLowDateTime: DWORD,
+    dwHighDateTime: DWORD,
+}
+
+#[repr(C)]
+struct BY_HANDLE_FILE_INFORMATION {
+    dwFileAttributes: DWORD,
+    ftCreationTime: FILETIME,
+    ftLastAccessTime: FILETIME,
+    ftLastWriteTime: FILETIME,
+    dwVolumeSerialNumber: DWORD,
+    nFileSizeHigh: DWORD,
+    nFileSizeLow: DWORD,
+    nNumberOfLinks: DWORD,
+    nFileIndexHigh: DWORD,
+    nFileIndexLow: DWORD,
+}
+
+#[repr(C)]
+struct SECURITY_ATTRIBUTES {
+    nLength: DWORD,
+    lpSecurityDescriptor: *mut std::ffi::c_void,
+    bInheritHandle: BOOL,
+}
+
+extern "system" {
+    fn CreateFileW(
+        file_name: LPCWSTR,
+        dwDesiredAccess: DWORD,
+        dwShareMode: DWORD,
+        lpSecurityAttributes: *mut SECURITY_ATTRIBUTES,
+        dwCreationDisposition: DWORD,
+        dwFlagsAndAttributes: DWORD,
+        hTemplateFile: HANDLE,
+    ) -> HANDLE;
+    fn GetFileInformationByHandle(
+        handle: HANDLE,
+        file_info: *mut BY_HANDLE_FILE_INFORMATION,
+    ) -> BOOL;
+    fn CloseHandle(handle: HANDLE) -> BOOL;
+    fn GetLastError() -> DWORD;
+}
+
+fn main() {
+    unsafe {
+        test_create_dir_file();
+        test_create_normal_file();
+    }
+}
+
+unsafe fn test_create_dir_file() {
+    let temp = utils::tmp();
+    let mut raw_path = temp.as_os_str().encode_wide().collect::<Vec<_>>();
+    // encode_wide doesn't add a null-terminator
+    raw_path.push(0);
+    raw_path.push(0);
+    let handle = CreateFileW(
+        raw_path.as_ptr(),
+        GENERIC_READ,
+        FILE_SHARE_READ | FILE_SHARE_WRITE,
+        ptr::null_mut(),
+        OPEN_EXISTING,
+        FILE_FLAG_BACKUP_SEMANTICS,
+        0,
+    );
+    assert_ne!(handle, -1, "CreateNewW Failed: {}", GetLastError());
+    let mut info = std::mem::zeroed::<BY_HANDLE_FILE_INFORMATION>();
+    if GetFileInformationByHandle(handle, &mut info) == 0 {
+        panic!("Failed to get file information")
+    };
+    assert!(info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY != 0);
+    if CloseHandle(handle) == 0 {
+        panic!("Failed to close file")
+    };
+}
+
+unsafe fn test_create_normal_file() {
+    let temp = utils::tmp().join("test.txt");
+    let mut raw_path = temp.as_os_str().encode_wide().collect::<Vec<_>>();
+    // encode_wide doesn't add a null-terminator
+    raw_path.push(0);
+    raw_path.push(0);
+    let handle = CreateFileW(
+        raw_path.as_ptr(),
+        GENERIC_READ | GENERIC_WRITE,
+        FILE_SHARE_READ | FILE_SHARE_WRITE,
+        ptr::null_mut(),
+        CREATE_NEW,
+        0,
+        0,
+    );
+    assert_ne!(handle, -1, "CreateNewW Failed: {}", GetLastError());
+    let mut info = std::mem::zeroed::<BY_HANDLE_FILE_INFORMATION>();
+    if GetFileInformationByHandle(handle, &mut info) == 0 {
+        panic!("Failed to get file information: {}", GetLastError())
+    };
+    assert!(info.dwFileAttributes & FILE_ATTRIBUTE_NORMAL != 0);
+    if CloseHandle(handle) == 0 {
+        panic!("Failed to close file")
+    };
+}